


An In-Depth Look at Imposter Anatomy

by FrostieFroakie



Series: Monsterfucker Collection [7]
Category: Dangan Ronpa - All Media Types, New Dangan Ronpa V3: Everyone's New Semester of Killing
Genre: Alien anatomy, Alternate Universe - Among Us (Video Game) Setting, Anal Sex, M/M, Not Beta Read, did i write this just because i wanted to give Ko a stomach maw? yes, i wanted to make imposter anatomy absolutely wild but i failed., my god did i fail, stomach mouth, this is a sequel to the other among us thing i wrote
Language: English
Status: Completed
Published: 2020-12-13
Updated: 2020-12-13
Packaged: 2021-03-11 03:06:40
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,426
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28058130
Author URL: https://archiveofourown.org/users/FrostieFroakie/pseuds/FrostieFroakie
Summary: Ever the curious type, Saihara get enamored by his new Imposter partner/boyfriend's body.
Relationships: Oma Kokichi/Saihara Shuichi
Series: Monsterfucker Collection [7]
Series URL: https://archiveofourown.org/series/1383685
Comments: 16
Kudos: 116





	An In-Depth Look at Imposter Anatomy

**Author's Note:**

> Hey, how's everyone doing. 2020 is almost over. We made it folks 😭
> 
> I think my writing muse and creativity has just straight up abandoned me u -u 
> 
> Well im glad i managed to finish this at least. Tbh, im kinda 'eh' about it but, hey, if you guys like it then thats good enough for me u vu

Just as Ouma thought, the moment they touched down in Mira HQ, he was almost immediately swarmed and snatched away from the remaining 3 survivors. It took a bit of convincing from Saihara to not just throw him out of the airlock so he can plummet to his death.

_“Saihara, that thing is an Imposter! It can’t stay here!”_

_“He won’t hurt anyone!”_

_“How do you know that?! Didn’t you lose 5 of your crewmembers to these things!?”_

_“Y-yes… but it had nothing to do with Ouma! Please, just give him a chance… If i’m wrong and he does end up killing someone then… I’ll let you all eject both of us.”_

That deal seemed to please the other crewmates enough to leave the pair alone, not without being watched constantly every time they were doing tasks in HQ of course… It made Ouma very antsy, especially since they separated the 2 of them every night to keep the Imposter on camera, but at least he had Saihara to keep him company and distract him from the many pairs of eyes that seemed to be locked on him at all times during the work days...

A week or so went by before the others seemed to relax enough around the docile Imposter. There was still an air of uncertainty, but it wasn’t nearly as tense as when they first landed, thankfully, so they allowed Ouma to bunk with Saihara since they were so comfortable with each other (and also, no one else wanted him in their room).

“You know Saihara,” Ouma piped up that night as they removed their suits for bed, “don’t you think them accepting your proposal to kill us both if a body is found so quickly was a bit… oh, I dunno, fucked up?” 

That was something that’s been bothering him the entire time, but he hasn’t really had any actual alone time with the human since they landed, what with him being constantly servallenced and them being separated at night.

“Well…. You’re not wrong but I knew they’d accept it without question. Losing one more crewmate wouldn’t really put a dent in anything and if it means getting rid of an Imposter as well, of course they’d accept it.”

“Again, really fucked up,” Ouma said as he stepped out of the suit and stretched. “And here I thought you humans were all~ about comradery.”

Saihara laughed a bitter laugh while he placed both suits in a decontamination closet. “Some of us are… Others will gladly sacrifice others in order to defeat the ‘bigger threat’... Or something…”

The Imposter quirked an eyebrow. The way he said that made it sound like he’s had some personal experience with being betrayed. “Hmhm… It explains why it’s so easy to manipulate you people then I suppose…” he mumbled as he removed the protective undershirt, a sigh of relief escaping him. “Finally I get to remove that thing! Jeez, it’s such a pain to wear all the time.”

“You get used to it…” the young human mumbled, completely ignoring the earlier comment. 

After removing his own undershirt, Saihara peeked at his roommate as the short boy kneaded at the bed like a giant cat. He’s never seen him without his suit so he was… curious. The first thing he noticed was his body shape. Ouma looked almost pear shaped with a scrawny chest, slightly pudgy looking belly and wide waist. He had thick thighs, his legs looked more powerful than his arms, and he had small claws on his hands and feets and a pretty plump looking-

“Are you checking me out?”

Saihara jumped, eyes widening as Ouma smirked at him.

“N-no! I just, I’ve never seen you without your suit and I-!”

Ouma laughed before sauntering over to Saihara and placing a hand on the other’s bare chest. “Aww…~ I don’t mind if you leer Shumai~ I know I’m definitely enjoying what I’m seeing~” he cooed, pressing his fingers on Saihara’s pecs and biceps.

He looked away as a deep red color covered his face. He wasn’t a bodybuilder by any means but he had built up plenty of natural muscle from his work. “I-I wasn’t leering… I was just curious…”

“Hmm… That so…~” Ouma snickered then took a few steps back, placing both arms behind his head. “Then who am I to deny you the opportunity to quench your curiosity, hm?~” he chuckled with a knowing glint in his eyes.

Saihara huffed, a small pout on his lips as he crossed his arms then looked towards Ouma from the corner of his eyes. The lack of a belly button and a long horizontal scar in its place caught his attention. It looked slightly curved upwards at the ends as if someone tried to carve him open and a look of concern took over his features. 

“Hm?” Ouma tilted his head, a confused frown replacing his earlier smirk, “What’s with that look?”

And much to Saihara’s shock, the ‘scar’ on his belly also shifted to somewhat match the frown on Ouma’s face. 

“Uhm… That… Did that scar just…. What?...”

“Scar?” Ouma looked down at his belly then snorted in amusement. “Oh I see now... Sweet Saihara, this isn’t a scar~”

Considering it just moved, he figured _that_ much. “Then what is-?” His words caught in his throat when the ‘scar’ opened slightly, revealing more shark-like teeth and a long, thick, sharp dark red tongue as it poked out. “.........oh,” Saihara breathed.

“Not quite the reaction I expected, but I am glad you’re not screaming in terror at least,” Ouma grinned brightly.

“Ahaha…. Well... I just keep reminding myself you’re not human is all… N-not that you scared me at all or anything, that’s just the excuse I use for anything… different,” he said, a pink blush on his face as he stared at his stomach maw. He always did have an attraction to the unknown…. And right now he wanted nothing more than to examine it more closely….

“My, my… you should see the look on your face… If you weren’t leering before you definitely are now~” Ouma giggled, the tongue hanging from his stomach mouth retracting before it closed and went back to looking like a slightly curved line. The Imposter walked backward towards the bed then hopped onto it before patting the spot next to him. “Come on lil’ kitty~ I can see how curious you are~”

Saihara’s blush darkened as he walked over and sat next to Ouma shyly. “Uh-uhm…”

“Go ahead… You wanna touch it right?~” Ouma purred.

“Hh… I’m that obvious huh….”

“Oh, I can read you like an open book,” he chuckled, looking the human up and down before taking one of his hands, pressing a kiss on it then placing it on his tummy. “Just… be gentle with me Shumai~ It’s my first time being touched down there…~” 

“D-dammit Ouma…..” Saihara grumbled, feeling his heart rate pick up from Ouma’s suggestive words and tone. He took a deep breath to calm himself down (nothing about this was sexual after all right? ... He was just touching his… stomach maw…) then started running his fingers along the slit, feeling him twitch and tremble slightly beneath his fingers, before pressing his fingers in one by one.

Ouma leaned back on his hands, a blush of his own starting to form on his cheeks and completely unknown to the man who was currently transfixed on watching his finger disappear into the extra cavity. 

The tongue slid out once again and wrapped itself around Saihara’s wrist before opening up wide enough for Saihara to get a better look at the inside. Other than the teeth and an area for the tongue to curl up, it looked more like a fleshy pocket. There was no ‘throat’ so anything that ended up in there most likely would just stay until they decided to remove it… Unless the thick saliva(?) would slowly erode whatever gets stuck in there…? Actually, where did the saliva go if there was no throat?

Saihara’s other hand rested under the bottom row of teeth, his thumb tracing the area where pale skin became pinkish-red flesh, as he leaned forward to get a closer look. His hand stroked the long appendage curiously, enjoying the smoothness of it. It didn’t _feel_ like an actual tongue with how smooth it was… Not to mention he clearly couldn’t eat anything with this mouth since there was no throat so... he wondered what the true purpose of this addition was... The tongue ended up pulling Saihara’s hand into the cavity and closing shut on it, not biting though, just poking and lapping away at his hand.

Ouma’s soft pants caught Saihara’s attention and his eyes widened slightly as he noticed the deep blush covering his face. “Ouma?...”

“Nn… I told you… I’ve never... had someone touch me there before…” he looked away, an embarrassed pout on his lips. “It’s really sensitive….” 

Saihara looked back down at his hand still trapped in that maw, his free hand gently rubbing the area. “I-I can stop if you wa-”  
  


“ _No_ , god no,” Ouma breathed, his head tilting to rest on top of his own shoulder, eyes half lidded and slightly clouded as his stomach mouth opened and the tongue unwrapped itself from Saihara’s wrist, allowing him to take his hand back and shake off some of the dribble dripping from it. “Keep touching me…. You want to know more about my body right?...~” he asked in a sly tone, his lips curling into a teasing smirk as his tongue poked out to lick at his own lips. He bent his legs and spread them, showing off the bulge in his boxers.

Saihara swallowed, his own dick hardening a bit at the erotic display, then nodded not trusting his voice right now.

“Then come closer… Let’s explore and play with each other some more~” 

Saihara nodded again then wasted no time, placing himself between Ouma’s legs and hovering over the other. He cleared his throat before asking shyly, “Can I kiss you?...”

Ouma fluttered his eyelashes and snickered as he laid back flat against the bed and pulled him down closer by his shoulders. “I’d be insulted if you didn’t…”

Saihara rolled his eyes then leaned forward and connected their lips in a soft kiss. It started out gentle and slow, like they were testing the waters before it became a more deeper and passionate kiss. Ouma’s tongue was longer and firmer than his own so he was able to dominate the kiss easily not that Saihara minded too much. The Imposter’s legs wrapped around his waist while his hands slid from his shoulders to his neck, his fingers entwining together while his thumbs gently rubbed along the length of his throat. A groan escaped them both when their crotches pressed together and Saihara rolled his hips forward to get more friction.

Ouma broke the kiss, his tongue still poking out from between his lips along with a little fang. He looked kinda cute like that… Saihara placed a kiss on his neck before sitting himself up, forcing Ouma to let go of his neck and slide his hand down to his chest. Golden eyes ran down his body, pausing briefly on the stomach maw that seemed to be drooling a little, then stopped at their still clothed pelvises. Saihara hooked his thumbs on the oddly colored underwear but hesitated in pulling them down.

A pair of clawed hands tapped his making him look up and see the impatient pout on his face. 

Saihara gave him a quick kiss on the nose before saying, “Can’t really blame me for being a bit nervous can you?...”

“Pfft, what?~ You telling me you’ve never had sex with a monster before?” he chuckled then lifted his hips slightly so Saihara could slide off his shorts.

“That’s what I’m telling you… I’m a monster virgin,” Saihara said jokingly as he pulled his shorts down. 

“Nishishi~ Aww, my darling has jokes…” he cooed, unwrapping his legs from the other’s waist so he can remove the shorts completely and allow his bedmate to get a good look at him.

His dick was the same dark red color as the tongue in his tummy mouth and, unlike a human, he apparently didn’t have a scrotum which means his testicles were hidden internally?… His cock did look like it slid out from a slit or sheath of some kind… Saihara tilted his head before holding onto his thighs and lifting him up slightly. His anus looked normal enough though…

“Shumai~”

“Hm?” 

“As much as I’m enjoying the attention… I’d really like it if you’d do more then just observe y’know?~”

Saihara sweatdropped with a smile before placing a kiss at the base of his cock getting a small squeak before placing him down. “Don’t be so impatient… You did say yourself that we should explore each other…”

“Mrr… Yeah, but I doubt I’m _that_ much different...” Ouma huffed then shot forward faster then Saihara could see, pushing him onto his back then yanking off his own shorts before he even got a chance to protest. 

“H-hey!” Saihara covered himself up instinctively, his face flaming.

“My turn to do some exploring~” he purred, patting at Saihara’s hands. “Are you really trying to hide from me? After I showed you my all? What, are you tiny or something?” he chuckled.

Saihara grumbled, “It was just instinctual… You caught me off guard with your speed…” then moved his hands away slowly, face flaming as Ouma ran his lust-filled gaze all over his body.

Ouma tilted his head when his sight reached his partner’s crotch, a confused look replacing the lusty look on his face. Before Saihara could question what was wrong, the Imposter placed his head between his legs and nipped at Saihara’s ballsack curiously.

“Ah! C-careful!”

“What’s this?”

“Th-that’s where human males keep their testicles…!”

“Huh? You just have these hanging out in the open like that?” Ouma gasped then crawled up before laying next to him. “A bit dangerous ain’t it?”

“Well... it’s not like we _chose_ to have them out like- hyahh!”

Saihara got cut off by the long tongue coming from Ouma’s tummy wrapping itself around his balls and dick and massaging them. The Imposter snickered at the look on his lover’s face. “Well~ I guess it does make it more convenient for me… But wow, you don’t even have protection for your dick either? Oh, you humans and your weird biology,” he hummed while the extra tongue continued rubbing and squeezing his cock and balls.

“Ahh… Y-you’re one to talk…” Saihara pouted glancing at the tongue fondling his crotch before looking down at Ouma’s erection then wrapping 3 fingers around it to stroke it up and down slowly, getting groans and purrs out of his partner. The tongue around his sensitive organs unwrapped from around them to lick messily at them, leaving his crotch thoroughly coated in the slimy saliva from his stomach mouth.

Meanwhile, Saihara was gently pumping Ouma’s cock as he ran his hand up and down until he got an idea. He pressed his index finger and thumb against the base until they breached the ring of muscle and allowed him to push the tips of his fingers into the sheath. Ouma immediately tensed up and for a second, he thought he may have hurt him, but the loud pleased squeal that escaped him when he rubbed the parts still hidden inside the protective slit told him otherwise. Even the extra tongue stopped licking at him and just hung there, quivering while Ouma squirmed against his fingers. He smiled then placed a hand on a pale waist before pushing his fingers in as deep as they could go. It wasn’t very far, only up to the first knuckle, but it was still enough to have Ouma completely melt in his hands. Saihara placed kisses all over the drooling alien’s face as his fingers felt around and rubbed along the hidden base. It felt kinda slimy but very warm in there...

Ouma crooned in pleasure, pressing himself closer to Saihara then running his fingers along his partner's cock before grabbing hold and stroking him quickly. Saihara’s moans joined his, albeit much softer and quieter than the Imposters, before it turned into a small yelp as Ouma pushed him onto his back and straddled him. Pale, clawed hands rested on Saihara’s chest while the Imposter gazed at him through half lidded eyes, his pupils blown wide and red mixing in with his natural purple eye color.

“Prr, No more teasing…~ Want you in me now!~”

Was he turning feral?...

Saihara placed a hand on Ouma’s waist while the other rested on his side. 

“D-don’t I have to prep you fir-”

“No,” Ouma said firmly, cutting him off, “no need for all that~...” then ran his hands down, his claws leaving light red scratches as he lifted his waist and pressed Saihara’s dick to his entrance. Before the human had a chance to protest, Ouma pushed himself down, sliding onto his cock rather easily. 

Saihara’s grip on Ouma tightened as the warmth and tightness of his ass wrapped around him. He bit his lower lip as a soft groan escaped him, his eyes flicking up to take in Ouma’s expression. The Imposter had a blissful look on his face, a loud purr coming from him while some drool slid down from both mouths. His second tongue dropped onto his belly as he lifted his hips and pushed himself before down quickly.

“Ngh! K-ko…!” Saihara grunted as Ouma kept up the quick pace.

The Imposter hummed and purred in pleasure as he bounced himself, his claws digging into his partner’s skin before he moved his hands to rest beside Saihara’s head. He flashed him a sharp tooth grin before leaning closer and rubbing their noses together, his long tongue sliding out to lick at Saihara’s lips before claiming them in a hot kiss. The hand on his side ran up to grip at his head as he kissed back, opening his mouth to allow their tongues to wrap around each other. 

Saihara shifted himself under Ouma slightly to make it easier to pound up into the tight ass, their moans muffled by their liplock. He could hear the sheets tearing from Ouma clenching onto them so tightly as he moved faster, the new angle allowing him to slide deeper into him. Ouma broke the kiss and buried his face in the crook of his lover’s neck, moaning directly into his ear before sinking his teeth into his shoulder and growling. Saihara flinched, a startled moan escaping him before he wrapped his arms around the other and rolled them over so Ouma was now under him.

The hands that were tearing holes into the sheets were now latched onto his back, claws digging dangerously into his skin, making Saihara stop and tense up. 

“Ko!.... C-careful…!” 

Ouma twitched then managed to force himself to unlatch his jaw and remove his hands before flopping onto the bed and panting, traces of his blood on Ouma’s mouth and teeth from where he bit him. 

“Hhnn… S-sorry… Just… feels good… sorry…” he panted out, hands clenching in the sheets again as he squirmed a bit under him.

Saihara sighed heavily before he looked at his shoulder to assess the damage. While he did feel a jolt from the bite, he didn’t notice he bit down deep enough to make him _bleed_. It didn’t look like anything that wouldn’t heal over a day or two… When he looked back at the Imposter, he looked sheepish and guilty.

“D-didn’t mean to hurt… can stop… i-if you want…” he mumbled, looking away.

Saihara blinked then cupped his cheek and turned his head back so he could look into those big, now fully red eyes with those dilated pupils and place a kiss on his nose. 

“I know you didn’t mean it… It’s fine, it’ll heal. And… I rather not stop now,” he whispered back, his thumb rubbing along Ouma’s lips and wiping off some of the blood. 

Ouma’s eyes flicked between the wound on his shoulder and his face multiple times before his tongue poked out and licked at his thumb and his own lips, cleaning the smeared blood off. 

“We just need to be more careful… ok Ko?…” he said gently then took both his wrists and held them above his head. 

Ouma nodded slowly, eyes sparkling as he glanced up at his bound wrists then back.

Saihara placed a soft kiss on his lips before his free hand gripped onto the back of his thigh, holding his leg up as he pulled out half way then slammed back in. Ouma tilted his head back and moaned loudly, the leg not being held wrapping around his waist. Saihara continued thrusting at a fast and strong pace while he littered kisses on his face, down to his neck, sucking at his skin to leave little hickeys here and there, and down to his chest. His stomach mouth was wide open, tongue hanging out and drooling profusely, the sticky substance leaking onto the bed and down the owner’s crotch. Tempting as it was to stick his hand inside that cavity to feel his soft, plush insides, he didn’t want to risk having his hand accidentally bitten off, so he just stroked the tongue then gripped Ouma’s leaking erection and rubbed him in between thrusts, giving him some firm pumps before breaching his sheath with his thumb once again to massage around the base. 

Ouma went wild in Saihara’s hold, back arching back arching off the bed, eyes rolling back, and his moans turning into yells and pleas for more. 

“Aahh!~ Shumai!!” 

Saihara panted, a groan coming from him as he pressed forward, the hand around his wrists tightening when he felt Ouma clench around his cock.

“More! More! Please! Shu-Ahhah!!”

Saihara moved his hand off Ouma’s dick to cup his cheek before he kissed him messily, muffling his moans as he pushed as deep as possible. He froze and gasped into the kiss when he felt Ouma’s extra tongue slide along his waist and between his booty cheeks to prod at his hole. He broke the kiss, eyes closed tightly as he moaned out,

“Ngh..! Kokichi…!”

“Mm, prrr~, so close… Need just… a little more…~” he cooed.

Saihara trembled a little as he felt it push past the ring of muscle and into him, wiggling a little as it forced its way a few inches deeper. It was… a foreign feeling. He can’t say he’s ever put anything in there before tonight. The slime made it real easy to slide into his virgin hole though so there was no pain, just weirdness and some discomfort… When he opened his eyes again, he was met with Ouma’s piercing gaze. He seemed to be watching him very carefully, the tip of his sharp tongue poking out from swollen lips set in a neutral line… until they curved into a devilish smile.

“No stopping…~” he purred then nipped at Saihara’s chin lightly before rocking his hips and pushing his tongue deeper in, drawing out another breathless moan from the man above him.

Saihara held onto Ouma’s thigh once again as he started moving again at a quick pace, his own moans matching Ouma’s in volume with the tongue thrusting and poking around at his insides. As soon as that wandering organ hit his prostate, he felt himself cum, unable to hold back from the jolt he felt from having that spot stimulated.

“AHH!”

Ouma gasped when he felt the warmth fill him, his head pressing into the bed as he came as well, his seed spurting out onto Saihara's tummy and into his own stomach maw. The tongue slid out of his partner slowly before retracting back into its cavity and snapping shut.

Saihara released Ouma's wrists before collapsing on top of him and panting into his neck. He felt Ouma run his fingers through his hair then felt his warm tongue run along the wound on his shoulder, cleaning it somewhat, He hummed softly then pulled out and rolled off when Ouma was done to lay beside him and snuggle him close. 

“...I’m still sorry about the bite…”

“I know. It’s no big deal, really,” Saihara pressed a kiss to his forehead.

Ouma blinked up at him, his eyes back to their purple color, then huffed as he looked away. “You just have no survival instincts whatsoever huh,” he mumbled in a deadpanned tone.

“I wouldn’t say that,” Saihara rolled his eyes. “It’s not like biting doesn’t happen during sex. You just need to learn to control your own strength is all. Until then, I’ll just have to keep you gagged and handcuffed every time we decide to be intimate.”

Ouma gave him an incredulous look before narrowing his eyes with a smirk. “You sound like you’re looking forward to that.”

Saihara hummed and tapped his fingers on Ouma’s waist before sliding them up to trace the line on his stomach. “I might be. I haven’t really finished mapping out your anatomy yet… I think there’s more here to explore,” he said simply as his hand then trailed down to run along his gential slit.

A shudder ran through Ouma as he pressed his face against Saihara’s chest and pouted, a blush coating his cheeks. “Well… I’m fine with letting you explore my body as many times as you want…” he purred gently. 

Saihara smiled then tilted Ouma’s head up to press a soft but deep kiss on his lips. The Imposter kissed back, a soft noise escaping his throat before he pulled away suddenly.

“We absolutely need a shower now though. I can feel your spunk leaking from my ass.”

“R-right….”

Bonus!

“Shuichi, why does your medical scan show multiple scratches and a large bite mark on your shoulder?...”

“...Uhh…”

“...Did that _thing_ attack you?!?”

“What?! No! Its… uhm...!”

“Oh, you humans and your constant jumping to conclusion…~ I think we all know what those marks are… But then again, maybe not? After all, I’m such an ugly, disgusting, vile creature and it’s not like there’s ever been any kind of attraction between me and my Shumai whatsoever.”

“...”

“...”

“Nah, not like we’d finally be so _happy_ to have each other to ourselves for once since reaching this station that emotions would peak and _things~_ would happen. Nope, never. Nishishi…~”

“...Shuichi-”

“He didn’t attack me. End of conversation.”

**Author's Note:**

> In that bonus part at the end I just imagine Kokichi sitting and flipping through a magazine or something while he talks lol
> 
> Maybe i should take a break from E rated stuff.... 🤔


End file.
